Currently, gateways with different functions are required in different network architectures. For example, in a 3rd Generation Partnership Project (3GPP) access scenario, a required gateway is an serving gateway (SGW) or a packet data network gateway (PGW). If the SGW and the PGW are considered as two function modules, the two function modules may be located in two independent entities, that is, the SGW and the PGW are two different gateways, or the two function modules may be located in a same entity, that is, the entity has functions of the SGW and the PGW.
Currently, the SGW supports forwarding of a data packet of, for example, General Packet Radio Service Tunneling Protocol (GTP) or Proxy Mobile Internet Protocol (PMIP), and the PGW supports forwarding of a data packet of, for example, the GTP, the PMIP, or Layer 2 Tunneling Protocol (L2TP). In an untrusted non-3GPP access manner, a required gateway is an evolved packet data gateway (ePDG), and the ePDG supports forwarding of a data packet of, for example, Internet Protocol security (IPsec), the GTP, or the PMIP. In a trusted non-3GPP access manner, a required gateway is a trusted access gateway (TGW), and the TGW supports forwarding of a data packet of, for example, generic routing encapsulation (GRE), layer 2 virtual local area network (VLAN), the GTP, or the PMIP.
Therefore, in different network architectures, multiple different gateways need to be deployed. In a multi-standard access architecture, there may be a relatively large quantity of gateway types. As a result, a network topology is complex and is difficult to maintain.